Topic: dual brake conversion updated

[void909]

I almost have all the parts i need to complete the list given here:
http://www.sohc4.net/index.php?title=Dual_disc_conversion
All I am lacking is the cb500/550 speedo drive plate.
http://cgi.ebay.com/ebaymotors/SPEEDOMETER-SPEEDO-DRIVE-CB500-HONDA-CB-500-T-TWIN_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247QQcategoryZ10066QQihZ001QQitemZ110235289303QQrdZ1QQsspagenameZWD1V#ebayphotohosting
Is this What I need or am I in the wrong ballpark?
(the word plate is throwing me off)
thanks
void

[crazypj]

Thats the drive gearbox, the plate bolts onto the wheel
PJ

[void909]

thanks PJ the hunt continues

[MCRider]

I almost have all the parts i need to complete the list given here:
http://www.sohc4.net/index.php?title=Dual_disc_conversion
All I am lacking is the cb500/550 speedo drive plate.
http://cgi.ebay.com/ebaymotors/SPEEDOMETER-SPEEDO-DRIVE-CB500-HONDA-CB-500-T-TWIN_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247QQcategoryZ10066QQihZ001QQitemZ110235289303QQrdZ1QQsspagenameZWD1V#ebayphotohosting
Is this What I need or am I in the wrong ballpark?
(the word plate is throwing me off)
thanks
void

In this schemaitc, its #33, the "retainer" which does not bolt to the wheel but is held there I think by #34 which bolts to the wheel. I made one for mine by grinding down the CB750 drive with a bench grinder to fit. There may not be enough room for #34.
http://www.bikebandit.com/houseofmotorcycles/honda-motorcycle-cb550-1974-front-wheel-rear-wheel/o/m9230sch396549

Scroll down to get the wheel diagram. I call it the "drive" as it has 2 dogs that hook into the wheel hub to turn the gearbox.

You may just order one from BikeBandit.

[void909]

Any idea if this is what I need. I know there is someone here that can verify this part for me. I thought this was a very popular upgrade??? ANY 750 guys in here got a part number or a link of the exact part or even better one in a bucket or on a shelf you want to get off of?
thanks
void

[mystic_1]

You need the 500/550 version of the circled part in the following pic.

The part number for the 500/550 part is (44641-341-000) RETAINER,GEAR BOX which is superceeded by 44641341000.  You get get either one from CMSNL: http://www.cmsnl.com/honda-cb500-500-four-k0-us_model459/partslist/F++07.html

cheers
mystic_1

[MCRider]

You need the 500/550 version of the circled part in the following pic.

The part number for the 500/550 part is (44641-341-000) RETAINER,GEAR BOX which is superceeded by 44641341000.  You get get either one from CMSNL: http://www.cmsnl.com/honda-cb500-500-four-k0-us_model459/partslist/F++07.html

cheers
mystic_1

+1 on that. Also, I read through the instructions in the post on assembling the dual discs and he does mention that you will not use the chrome dress plate that is held on by the bolts. There is no room. That was my memory as well. I did mine years ago. and the stock CB750 "retainer, gear box" which I call the "drive plate" can be modified to work with a bench grinder though its not as slick asthe 550 part.

[crazypj]

I had to do some pretty major modifications to that part to make it work on 1977 CB550 F1.
Don't know if the earlier models are different?
PJ

[Shenanigans]

I thought I remember reading that the superceeded speedo drive would not work and that you needed the "Original" one to work?




Turns out it was on the 550 dual disk article so I guess it does not matter on the 750's?

[bryanj]

I'll say it one more time----

THE 500/550 DRIVE IS EXACTLY THE SAME AS THE 750 ONE

What you need is the VERY early 750 one which was "improved" to the one in the picture!

There is/was a dual disc conversion how to I wrote with pictures of the two different plates, PM me with your email address if you want a copy.

And you cant use the chrome cover that holds the drive plate to the wheel!

[cben750f0]

hey guys, yeah have since been told that the part that fits into the centre of the disc is a very early part, that is no longer made, the  reason i said that it was a 500/550 part, was when i bought it, it was advertises as such, sorry for the miss information.

the 750 drive place can be modified if you know a machin shop, turn the down to fit in the centre of the disc, then bend one edge so that it engages the flats on the hub. there is no stress on the part, so this should be enough.

And now you cannot use the dress ring, the second disc takes up the place that it would have resided..

hope this helps.

peace

[MCRider]

hey guys, yeah have since been told that the part that fits into the centre of the disc is a very early part, that is no longer made, the  reason i said that it was a 500/550 part, was when i bought it, it was advertises as such, sorry for the miss information.

the 750 drive place can be modified if you know a machin shop, turn the down to fit in the centre of the disc, then bend one edge so that it engages the flats on the hub. there is no stress on the part, so this should be enough.

And now you cannot use the dress ring, the second disc takes up the place that it would have resided..

hope this helps.

peace

I did my modifications with a bench grinder. Ground off the outside leaving enough to bend down the tabs as you mentioned with a torch and vice grips. VERY crude but worked perfectly.

[bwaller]

For a visual

[bryanj]

Good pic, better than the one i put in the how to anyway,
BE ADVISED that in some cases you have to slightly "modify" the internal circle of the disc on the speedo side for the bent down "Ears" to fit in

[void909]

Thanks Bwaller and Bryanj for your help and pics. I just don't know if i can pull off this mod. I have a bench grinder, but I'm just not sure about the heating and bending part.

[hymodyne]

I used a dremel with a reinforced cutting disc to make the mods to my speedo hub.

hym

[void909]

Hymodyne, You didn't use heat at all? Ok... By looking at Bwaller's pic, It looks to me like I can get this shape without bending anything. If I just grind down the lip and leave the tabs where they are, then cut off the tabs with a dremel to fit do you guys think this would work?

Bwaller, just to be clear, how did you modify your plate?

Thanks for your help guys. I almost have worked up the balls to grind this thing.

[bwaller]

No you don't need any heat. Just make sure that the tabs are not too tight a fit in the hub. There should be a small amount of free play to allow the drive plate to center once the axle is in place.

[void909]

Alright, I'm going to give it a shot.

Thanks for the help guys. Ill let you know how it goes.

[MCRider]

Hymodyne, You didn't use heat at all? Ok... By looking at Bwaller's pic, It looks to me like I can get this shape without bending anything. If I just grind down the lip and leave the tabs where they are, then cut off the tabs with a dremel to fit do you guys think this would work?

Bwaller, just to be clear, how did you modify your plate?

Thanks for your help guys. I almost have worked up the balls to grind this thing.

i thought so at first as well. But I think you may find (and I'm working from memory here) that you have to grind down the outside diameter so far that you will remove the natural shoulder, to fit inside the new disc. So bending tabs is still necessary. Cold bend will work, I just thought some heat may add to it. Pictures to follow. Mine is so crude its embarrasing, but it worked for many years till i parked it.

Apologies for pitiful picture. The one on the left I had made by a machinist. he welded on little rectangular bars as the tabs. The OD was turned down in a mill. Very nice. he even welded in a little bushing to the inside to make it fit tighter on the axle. Completely unnecessary, but machinists are sometimes anal.

The one on the right is the one I ground down then bent some tabs into it with ViceGrips. Worked for as long as the bike ran, 50K miles. Very crude.

[void909]

Thanks MCrider1. These pics help a lot too. My drilled rotors should be in this week. Once I get them in I will mock them up on the spare hub I have and start grinding. Quick question. Where did you guys get your hardware for this conversion? I spoke to a new member of the forum who is a Wurth rep who said he could get all the hardware in stainless steel but he can only do it in bulk. I posted to see if there was any other members interested in these parts but I got no takers. I wasn't trying to make any money I just thought someone else would be interested. Anyway does anyone know where to get this stuff? thanks again void.

[MCRider]

Thanks MCrider1. These pics help a lot too. My drilled rotors should be in this week. Once I get them in I will mock them up on the spare hub I have and start grinding. Quick question. Where did you guys get your hardware for this conversion? I spoke to a new member of the forum who is a Wurth rep who said he could get all the hardware in stainless steel but he can only do it in bulk. I posted to see if there was any other members interested in these parts but I got no takers. I wasn't trying to make any money I just thought someone else would be interested. Anyway does anyone know where to get this stuff? thanks again void.

First of all, this place which was a SOHC4.net referral has a $15 minimum so they may work: http://www.metricscrew-toolco.com/

Secondly, I got mine from ACE hardware if memory serves 28 years ago. I think it requires thin nuts so keep that in mind. A bench grinder did it for me once again.

Thirdly, Stainless Steel is not appropriate for this application from an engineers standpoint. I learned that SS is actually weaker than traditional steel bolts, and they don't have the resistance to sheer loads that is required. As a practical matter, probably OK to use, since you don't know where I live. 

I haven't gone hardware shopping for my project yet, but MetricScrew-toolco above looks like the place. I want to get harder bolts made up for motor mounts.

[void909]

[/quote]
First of all, this place which was a SOHC4.net referral has a $15 minimum so they may work: http://www.metricscrew-toolco.com/

Secondly, I got mine from ACE hardware if memory serves 28 years ago. I think it requires thin nuts so keep that in mind. A bench grinder did it for me once again.

Thirdly, Stainless Steel is not appropriate for this application from an engineers standpoint. I learned that SS is actually weaker than traditional steel bolts, and they don't have the resistance to sheer loads that is required. As a practical matter, probably OK to use, since you don't know where I live. 

I haven't gone hardware shopping for my project yet, but MetricScrew-toolco above looks like the place. I want to get harder bolts made up for motor mounts.
[/quote]

I just sent them an email to see if they had the hardware. Ill grind them if I have to. I appreciate the stainless steel tip, Ron from Indianapolis IN. I will not be getting Stainless steel if that is the case. No wonder nobody was interested in the parts, they probably thought I was trying to kill them. thanks MCRider1
void909

[crazypj]

From what I remember, heating isn't a good idea to bend tabs down as the center piece is bonded into the outer ring with some type of rubber which gets burned up. I managed to repair mine with some self vulcanising rubber, but it took a couple of weeks to fully cure and failed after about 5 yrs ( when I did it over)
Cold bending is a better way to go but I had a drive flange crack doing that as well. I'm going to make a new drive flange one day so I don't get any more problems
PJ

[MCRider]

From what I remember, heating isn't a good idea to bend tabs down as the center piece is bonded into the outer ring with some type of rubber which gets burned up. I managed to repair mine with some self vulcanising rubber, but it took a couple of weeks to fully cure and failed after about 5 yrs ( when I did it over)
Cold bending is a better way to go but I had a drive flange crack doing that as well. I'm going to make a new drive flange one day so I don't get any more problems
PJ

Was that on a CB750? No rubber anywhere near my part.